European white stork migration routes
Winter areas
The researchers say that Euro
pean white storks do a helpful job in
parts o f Africa, south o f the Sahara.
There, they feed on insects that can
damage, or destroy, food crops. Lo
custs are an example. If more storks
decide not to migrate, it could cause
problems for farmers in southern
Africa. D
W
h a t
m a d e
the
M
o o n
?
Researchers from America have car
ried out a new study. They compared
‘chemical fingerprints’ in Moon
rocks and rocks from the Earth. The
researchers wanted to find out if the
rocks were the same or different.
A popular theory says that the Moon
was created after another planet hit,
or collided with, the Earth. Some
scientists suspect that this was a
direct hit. Others believe it hit the
Earth at an angle. Therefore it was
a glancing blow. Pieces o f the Earth
and the other planet then merged, or
coalesced, to form the Moon.
The Moon is much larger than the
moons, or natural satellites, o f the
Solar System’s other planets. Jupiter
and Saturn have over 60 satellites.
M ost are very small. Some moons
were formed at the same time as
the planets they circle. Others were
caught, or captured, by a larger
planet’s gravity at a later time.
The M oon’s size is unusual. It
is almost one-third the size o f the
Earth. There are several theories,
or ideas, that explain why a planet
the size o f the Earth has such a large
satellite. The theory about the Earth
being hit by another planet was first
suggested about 30 years ago. This
‘other’ planet has even been given a
name. It’s called Theia (pronounced
thay-eh). Theia was about the same
size as Mars. In Greek mythol
ogy, Selene was the goddess o f the
Moon. Theia was her mother.
The Solar System is about 4.6
billion years old. The collision be
tween the Earth and Theia happened
4.5 billion years ago. Then, the Earth
was new-born, or a proto-planet. It
was only 100 million years old.
Nearly 100% o f the Earth’s oxy
gen is w hat’s known as O-16. This
means that each oxygen atom has
eight protons and eight neutrons. So
far, rocks found from other planets
in the Solar System have different
oxygen isotopes. In rocks, these iso
topes are sometimes called ‘chemi
cal fingerprints’.
The researchers studied rocks
brought back from the M oon by
the Apollo 12, 15 and 17 missions.
These missions were part o f N A
SA’s Apollo space program. Apollo
11 was the first M oon landing. A n
cient Greeks and Romans believed
that Apollo was one o f the most
important gods. He was the son of
Zeus, or the king o f the gods. Apol
lo was god o f many things. These
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